What is the difference between the order of a reaction with respect to a given species and the overall order?

Hydrogen bromide is a compound of the two elements hydrogen and bromine. It melts at $-87^{\circ} \mathrm{C}$ and boils at $-67^{\circ} \mathrm{C}$. It has the same type of bonding as hydrogen chloride.

a. Is hydrogen bromide a solid, a liquid, or a gas at room temperature $\left(20^{\circ} \mathrm{C}\right)$ ?

b. Is hydrogen bromide molecular, or does it have a giant structure? What is your evidence?

c. i. Which type of bond is formed between the hydrogen and bromine atoms, in hydrogen bromide?

ii. Draw a diagram of the bonding between the atoms, showing only the outer electrons.

d. Write a formula for hydrogen bromide.

e. i. Name two other compounds with bonding similar to that in hydrogen bromide.

ii. Write formulae for these two compounds.

Hydrogen and bromine react reversibly:

$$\mathrm{H}_2(g)+\mathrm{Br}_2(g) \rightleftharpoons 2 \mathrm{HBr}(g)$$

a. Which of these will favour the formation of more hydrogen bromide?

i. add more hydrogen

ii. remove bromine iii remove the hydrogen bromide as it forms

b. Explain why increasing the pressure will have no effect on the amount of product formed.

c. However, the pressure is likely to be increased, when the reaction is carried out in industry. Suggest a reason for this.

A reaction has a rate constant of 0.000122/s at 27$^{\circ} \mathrm{C}$ and 0.228/s at 77$^{\circ} \mathrm{C}$. a. Determine the activation barrier for the reaction. b. What is the value of the rate constant at 17$^{\circ} \mathrm{C}$?

The tabulated data show the rate constant of a reaction measured at several different temperatures. Use an Arrhenius plot to determine the activation barrier and frequency factor for the reaction.

$$\begin{matrix} \text{Temperature (K)} & \text{Rate Constant (1/s)}\\ \text{300} & \text{0.0134}\\ \text{310} & \text{0.0407}\\ \text{320} & \text{0.114}\\ \text{330} & \text{0.303}\\ \text{340} & \text{0.757}\\ \end{matrix}$$

What is the value of the rate constant?

The tabulated data show the rate constant of a reaction measured at several different temperatures. Use an Arrhenius plot to determine the activation barrier and frequency factor for the reaction.

$$\begin{matrix} \text{Temperature (K)} & \text{Rate Constant (1/s)}\\ \text{310} & \text{0.00434}\\ \text{320} & \text{0.0140}\\ \text{330} & \text{0.0421}\\ \text{340} & \text{0.118}\\ \text{350} & \text{0.316}\\ \end{matrix}$$

Cyclopro pane ($C_3H_6$) reacts to form propene ($C_3H_6$) in the gas phase. The reaction is first or der in cyclo propane and has a rate constant of $5.87 \times 10^{-4} / \mathrm{s}$ at 485 $^{\circ} \mathrm{C}$. If a 2.5- L reaction vessel initially contains 722 torr of cycloprop ane at 485$^{\circ} \mathrm{C}$, how long will it take for the partial pressure of cyclopropane to drop to be low $1.00 \times 10^{2}$ torr?

Ethyl chloride vapor decomposes by the first-order reaction: $\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{Cl} \longrightarrow \mathrm{C}_{2} \mathrm{H}_{4}+\mathrm{HCl}$ The activation energy is 249 kj/mol, and the frequency factor is $1.6 \times 10^{14} s^{-1}$. Find the value of the rate constant at 710 K. What fraction of the ethyl chloride decomposes in 15 minutes at this temperature? Find the temperature at which the rate of the reaction would be twice as fast.

Consider the first-order decomposition of cyclobutane at $438^{\circ} \mathrm{C}$ at constant volume: $\mathrm{C}_4 \mathrm{H}_8(g) \rightarrow 2 \mathrm{C}_2 \mathrm{H}_4(g)$ a. Express the rate of the reaction in terms of the change in total pressure as a function of time. b. The rate constant for the reaction is $2.48 \times 10^{-4} \mathrm{~s}^{-1}$. What is the half-life? c. After initiation of the reaction, how long will it take for the initial pressure of $\mathrm{C}_4 \mathrm{H}_8$ to drop to $90 \%$ of its initial value?

What is the relationship between the parameters in the Arrhenius equation and in the Eyring equation?

What is a typical rate constant for a diffusion-controlled reaction in aqueous solution?

What is meant by a diffusion-controlled reaction?

A convenient source of gamma rays for radiation chemistry research is ${ }_k^{60} \mathrm{Co}$, which undergoes the following decay process: ${ }_{27}^{60} \mathrm{Co} \stackrel{k}{\rightarrow}{ }_{28}^{60} \mathrm{Ni}+\beta^{-}+\gamma$. The half-life of ${ }^{60} \mathrm{Co}$ is $1.9 \times 10^3$ days. a. What is the rate constant for the decay process? b. How long will it take for a sample of ${ }^{60} \mathrm{Co}$ to decay to half of its original concentration?